scale all parameters in an attempt to fix artifacts

src/entities/Sky.svelte

@@ -66,18 +66,20 @@
     return null
   }
 
+  $: scale = 1e-6
+  $: Sky.cameraScale = scale
   $: Sky.moonTexture = getTexture(textures, $selectedMoon)
   $: Sky.sunIntensity = $sunIntensity
-  $: Sky.rayleighCoefficients = $rayleighCoefficient
-  $: Sky.rayleighScaleHeight = $rayleighScaleHeight
-  $: Sky.mieCoefficients = $mieCoefficient
+  $: Sky.rayleighCoefficients = $rayleighCoefficient.clone().multiplyScalar(1/scale)
+  $: Sky.rayleighScaleHeight = $rayleighScaleHeight * scale
+  $: Sky.mieCoefficients = $mieCoefficient.clone().multiplyScalar(1/scale)
   $: Sky.mieWavelengthResponse = $mieWavelengthResponse
-  $: Sky.mieScaleHeight = $mieScaleHeight
+  $: Sky.mieScaleHeight = $mieScaleHeight * scale
   $: Sky.mieDirectional = $mieDirectional
   $: Sky.mieBaseline = $mieBaseline
-  $: Sky.ozoneLayerHeight = $ozoneLayerHeight
-  $: Sky.ozoneLayerWidth = $ozoneLayerWidth
-  $: Sky.ozoneCoefficients = $ozoneCoefficients
+  $: Sky.ozoneLayerHeight = $ozoneLayerHeight * scale
+  $: Sky.ozoneLayerWidth = $ozoneLayerWidth * scale
+  $: Sky.ozoneCoefficients = $ozoneCoefficients.clone().multiplyScalar(1/scale)
   // $: Sky.exposure = $exposure
   $: Sky.iSteps = $iSteps
   $: Sky.jSteps = $jSteps
@@ -88,14 +90,14 @@
   $: Sky.cloudThreshold = $cloudThreshold
   $: Sky.cloudAbsorption = $cloudAbsorption
   $: Sky.windSpeed = $windSpeed
-  $: Sky.atmosphereThickness = $atmosphereThickness
-  $: Sky.planetRadius = $planetRadius
-  $: Sky.sunPosition.set(...$sunPosition)
-  $: Sky.sunRadius = $sunRadius / METER
-  $: Sky.moonPosition.copy($moonPosition)
-  $: Sky.moonRadius = $moonRadius / METER
+  $: Sky.atmosphereThickness = $atmosphereThickness * scale
+  $: Sky.planetRadius = $planetRadius * scale
+  $: Sky.sunPosition.set(...$sunPosition).multiplyScalar(scale)
+  $: Sky.sunRadius = $sunRadius / METER * scale
+  $: Sky.moonPosition.copy($moonPosition).multiplyScalar(scale)
+  $: Sky.moonRadius = $moonRadius / METER * scale
   $: Sky.fisheye = fisheye
-  $: Sky.uAltitude = $altitude
+  $: Sky.uAltitude = ($altitude + 1) * scale
 
   // $: Sky.shader.blendEquation = $altitude > $atmosphereThickness * 0.9 ? THREE.AddEquation : THREE.MaxEquation
 

src/shaders/sky/Sky.js

@@ -33,6 +33,7 @@ export default () => {
 
   const uniforms = {
     opacity: 1,
+    cameraScale: 1,
     planetColor: new THREE.Color(0x111111),
     moonPosition: new THREE.Vector3(0, 0, 0),
     moonRadius: 0.2727 * Re,

src/shaders/sky/fragment.glsl

@@ -606,7 +606,7 @@ vec4 scattering(
     opacity = mix(1., opacity, avgUmbra);
   }
   // add the clouds
-  color = color * (1. - cloudAbsorptionAmount)  + cloud;
+  color = color * (1. - cloudAbsorptionAmount) + cloud;
   return vec4(I0 * clamp(color, 0.0, 1.0), clamp(opacity, 0.0, 1.0));
 }
 
@@ -630,7 +630,8 @@ void main() {
 
   // if the ray intersects the planet, return planet color
   bool planet_intersected = intersectsInside(intPlanet);
-  if (altitude < 2000.){
+  float z = altitude / atmosphereThickness;
+  if (z < 0.025){
     if(planet_intersected) {
       gl_FragColor = vec4(planetColor, 1.);
       return;
@@ -656,7 +657,7 @@ void main() {
 
   // as we get closer to the planet, the atmosphere should get darker
   if (planet_intersected){
-    float k = remap(altitude, 2000., 4000., 0., 1.);
+    float k = remap(z, 0.025, 0.05, 0., 1.);
     color = mix(vec4(planetColor, 1.), color, k);
   } else {
     // color = color * (1.0 + 0.8 * fbm(vUv * 100.));

src/shaders/sky/vertex.glsl

@@ -9,6 +9,7 @@ varying float altitude;
 varying vec3 origin;
 varying float sunVisibleArea;
 
+uniform float cameraScale;
 uniform bool fisheye;
 uniform float uAltitude;
 uniform vec3 sunPosition;
@@ -29,7 +30,8 @@ void main() {
   gl_Position.z = gl_Position.w; // set z to camera.far... not sure why though
 
   origin = (modelMatrix * vec4(0.0, 0.0, 0.0, 1.0)).xyz;
-  rayOrigin = fisheye ? vec3(0., planetRadius + uAltitude + 1.0, 0.0) : cameraPosition - origin + vec3(0, 1.0, 0);
+  rayOrigin = fisheye ? vec3(0., planetRadius + uAltitude, 0.0) : (cameraPosition - origin + vec3(0, 1.0, 0)) * cameraScale;
+  // rayOrigin = vec3(0., planetRadius + uAltitude, 0.0);
   altitude = length(rayOrigin) - planetRadius;
   vec3 groundOrigin = normalize(rayOrigin) * planetRadius;